A biometric authentication that uses various types of biometric information is known. Biometric information is, for example, information about a palm print, which is wrinkles on the surface of a palm, information about veins in the palm, information about a palm shape such as the width of the palm, the lengths of fingers, and the shape of the outline of a hand, information about fingerprints, and information about an iris. In Non-patent Literature 1 (David D. Zhang “Palmprint Authentication”, Springer, 2004), for example, a technology of palm authentication is disclosed that uses biometric information extracted from an image of a palm.
A communication device in which a biometric authentication function is mounted has also been developed in recent years. In Patent Literature 1 (Japanese Patent No. 5509459), for example, a mobile terminal is disclosed that extracts biometric information such as a vein pattern and a palm print shape from image data and uses the biometric information to perform authentication. A camera mounted in the mobile terminal captures the image data.